﻿using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;

namespace XbsWebAPI.Application
{
    /// <summary>
    /// 枚举转换为字典
    /// </summary>
    public class EnumToDictionaryManager
    {
        // <summary>
        /// 扩展方法,获得枚举的Description
        /// </summary>
        /// <param name="value">枚举值</param>
        /// <param name="nameInstead">当枚举值没有定义DescriptionAttribute,是否使用枚举名代替,默认是使用</param>
        /// <returns>枚举的Description</returns>
        public static string GetDescription<T>(Object value, String otherDesc = "", Boolean nameInstead = false)
        {
            var type = typeof(T);
            if (!type.IsEnum)
            {
                throw new ArgumentException("该对象不是一个枚举类型！");
            }
            string name = Enum.GetName(type, Convert.ToInt32(value));
            if (name == null)
            {
                return otherDesc;
            }
            FieldInfo field = type.GetField(name);
            DescriptionAttribute attribute = Attribute.GetCustomAttribute(field, typeof(DescriptionAttribute)) as DescriptionAttribute;
            if (attribute == null && nameInstead == true)
            {
                return name;
            }
            return attribute == null ? otherDesc : attribute.Description;
        }

        /// <summary>
        /// 把枚举转换为键值对集合
        /// </summary>
        /// <param name="enumType">枚举类型</param>
        /// <param name="getText">获得值得文本</param>
        /// <returns>以枚举值为key，枚举文本为value的键值对集合</returns>
        public static Dictionary<Int32, String> EnumToDictionary<T>(EnumAppendItemType appendType = EnumAppendItemType.None)
        {
            var enumType = typeof(T);
            if (!enumType.IsEnum)
            {
                throw new ArgumentException("传入的参数必须是枚举类型！", "enumType");
            }
            Dictionary<Int32, String> enumDic = new Dictionary<int, string>();
            int appendId = Convert.ToInt16(appendType);
            if (appendType != EnumAppendItemType.None)
            {
                enumDic.Add(-999, GetDescription<EnumAppendItemType>(appendId));
            }

            Array enumValues = Enum.GetValues(enumType);
            foreach (Enum enumValue in enumValues)
            {
                Int32 key = Convert.ToInt32(enumValue);
                String value = GetDescription<T>(key);
                enumDic.Add(key, value);
            }
            return enumDic;
        }


        public enum EnumAppendItemType
        {
            None = -999,
            [Description("--所有--")]
            All = 1,
            [Description("--请选择--")]
            Select = 2,
        }
        ///
        　　/// 访问设备
        　　 ///
        public enum DeviceType
        {
            [Description("PC")]
            PC = 1,
            [Description("移动端")]
            Mobile = 2
        }
    }
}
